This study investigated the associations among psychologically controlling parenting, relational aggression, friendship quality, and loneliness during adolescence. A model was proposed in which relational aggression plays an intervening role in the relations between both parental psychological control and friendship outcomes. In a sample comprised of middle adolescents and their parents, process analyses revealed that psychological control (indexed by parent and adolescent reports) positively predicted adolescents' self-reported relational aggression that, in turn, negatively predicted friendship quality and positively predicted loneliness. The model held for both mothers and fathers and was not moderated by adolescent gender. The discussion focuses on possible mechanisms explaining the relations among psychological control, relational aggression, and friendship outcomes.